Another example of a supercar that’s also socially-responsible. Porsche has given the go signal on the development of the 918 Spyder, a plug-in hybrid said to give you up to 94.1 miles to the gallon. If that’s not impressive, then the 70 grams/kilometer of CO2 emissions must surely be noteworthy to you. Don’t forget, this is still a supercar that can still take you out on a very long vacation if you’re not careful in handling it. ~$600,000.